Double ended intravascular medical device

ABSTRACT

An intravascular medical device including an elongated member configured to be advanced along a vascular path of a patient, the elongated member having opposite first and second ends, the first end and second ends both being adapted for intravascular insertion, and the first end having a different structure than the second end. The elongated member has sufficient flexibility to be advanced through a human vasculature. Preferably, the first and second ends are adapted to have different operating characteristics. Depending on the operating characteristics needed for a particular procedure, a physician can insert either the first end portion or the second end portion of the elongated member into the patient&#39;s vasculature.

This application is a continuation of U.S. application Ser. No.10/810,445, filed Mar. 26, 2004, now U.S. Pat. No. 7,637,920 B2, issuedDec. 29, 2009, which claims the benefit of U.S. Provisional ApplicationNo. 60/458,884, filed Mar. 28, 2003, entitled “Double EndedIntravascular Medical Device,” and U.S. Provisional Application No.60/508,437, filed Oct. 3, 2003, entitled “Variable Diameter DeliveryCatheter,” the contents of each of which are hereby incorporated byreference herein.

FIELD OF THE INVENTION

The present invention is related generally to medical devices. Morespecifically, the present invention is related to intravascular medicaldevices such as catheters and guidewires.

BACKGROUND OF THE INVENTION

Blood vessel disease is a significant cause of premature disability anddeath. Heart attacks, strokes and other ailments are often caused byblood vessel disease.

The most common disease of the blood vessels is atherosclerosis.Atherosclerosis involves the accumulation of plaques of cholesterol,lipids and cellular debris within an artery. As the plaque accumulates,the artery wall thickens thereby narrowing the lumen of the artery. Asthe lumen narrows, the blood flow to tissue nourished by the artery isdiminished. The development of plaques can also contribute to theformation of emboli or thrombi. An embolus is a moving obstruction suchas a platelet aggregate. A thrombus can be a fixed obstruction such as awall adherent blood clot or can become an embolus. A thrombus or emboluswithin a coronary artery can occlude the artery thereby causingmyocardial infarction, angina and other conditions. A blockage caused bya thrombus or embolus within a vessel supplying blood to the brain canlead to a stroke. Renal, peripheral, and other blood vessels can alsobecome blocked by an embolus or a thrombus thereby causing tissue damagedownstream of the blockage.

A number of medical procedures have been developed to allow for theremoval of plaque from vessel walls or to clear a channel throughplaque, thrombus or clot to restore blood flow. For example, atherectomyor thrombectomy devices can be used to remove atheroma or thrombus.Vessel restrictions can also be treated with grafts that bypass therestrictions. Alternatively, balloon angioplasty and stenting procedurescan be used to enlarge the lumen size of a vessel at an obstruction.

In a typical angioplasty procedure, a guide wire and guide catheter areinserted into a vessel of a patient. An inflatable balloon is thenpushed through the guide catheter and advanced across a stenosis orblockage. Once positioned at the blockage, the balloon is inflated todilate the blockage and open a flow channel through the partiallyblocked vessel region. One or more stents may also be placed across thedilated region or regions to reinforce the expanded vessel segment or tomaintain dilatation of a vessel segment.

While some stenoses remain adherent to the vessel wall during treatment,others are more brittle, and may partially crack and fragment duringtreatment, allowing the fragments to flow downstream where they mayblock more distal and smaller vessels. Consequences of embolizationinclude myocardial infarction, stroke, diminished renal function, andimpairment of peripheral circulation possibly leading to pain andamputation.

Embolic protection devices have been developed to prevent the downstreamtravel of materials such as thrombi, grumous, emboli, and plaquefragments. Devices include occlusive devices and filters and may bedeployed distal to a treatment site or proximal to a treatment site.Occlusive devices, for example distal inflatable balloon devices, cantotally block fluid flow through the vessel. The material trapped by theinflatable devices can remain in place until removed using a method suchas aspiration. Occlusive devices can also be deployed proximal to atreatment site and flow reversed or stopped at the treatment site.Following treatment emboli are carried by flow out of the vesseltypically through a catheter and out of a patient. Filters can allowperfusing blood flow during the emboli capture process. The filters canbe advanced downstream of a site to be treated and expanded to increasethe filter area. Emboli, such as grumous or atheroma fragments, can becaptured in the filter until the procedure is complete or the filter isoccluded. When the capacity of the filter is reached, the filter maythen be retracted and replaced.

Embolic protection devices can be delivered over guide wires and withinguide catheters. The embolic protection methods are normally practicedancillary to another medical procedure, for example angioplasty withstenting or atherectomy. The embolic protection procedure typicallyprotects downstream regions from emboli resulting from practicing thetherapeutic interventional procedure.

SUMMARY OF THE INVENTION

One inventive aspect of the present disclosure relates to a medicaldevice comprising an elongated member configured to be advanced along avascular path of a patient, the elongated member having opposite firstand second ends, the first end and second ends both being adapted forintravascular insertion, and the first end having a different structurethan the second end. The elongated member has sufficient flexibility tobe advanced through a human vasculature. Preferably, the first andsecond ends are adapted to have different operating characteristics.

Depending on the operating characteristics needed for a particularprocedure, a physician can insert either the first end portion or thesecond end portion of the elongated member into the patient'svasculature. The intravascular medical device can include any number ofdifferent types of devices used in the treatment of vascular disease.Example devices include guide wires, catheters, embolic protectiondevice delivery systems and embolic protection device retrieval systems.

The invention provides a method for positioning a catheter within apatient's blood vessel, the method comprising: providing a cathetercomprising an elongated member configured to be advanced along avascular path of a patient, the elongated member having opposite firstand second ends, the first end and second ends both being adapted forintravascular insertion, the first end comprising a delivery sheath, thesecond end comprising a retrieval sheath, the delivery sheath comprisingat least one sidewall port adapted for receiving a wire, and thecatheter having a lumen between the first end and the at least onesidewall port; providing a guide wire having a proximal end and a distalend; advancing the guide wire to a target site within the patient'sblood vessel; and advancing the catheter over the guide wire byinserting the guide wire through the catheter lumen between the firstend and the at least one sidewall port.

The invention provides a guide wire loading assist device comprising: amember having a proximal first and a distal second end and a lumentherebetween, the lumen being adapted to encase a catheter having asidewall port adapted for receiving a wire; and a sidewall port in themember adapted for receiving a wire, wherein the lumen of the member hasa first axial orientation from the proximal first end to the sidewallport of the member and a second axial orientation from the sidewall portof the member to the distal second end, the different axial orientationsforming a bend in the lumen near the sidewall port, the sidewall port ofthe member being adapted to be coincident with the sidewall port of thecatheter.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 schematically shows a medical device having features that areexamples of inventive aspects in accordance with the principles of thepresent disclosure.

FIG. 2 shows a double-ended catheter having features that are examplesof inventive aspects in accordance with the principles of the presentdisclosure.

FIG. 3 shows the catheter of FIG. 2 with a delivery end of the cathetercontaining an emboli protection device, the delivery end is locatedadjacent to an ostium.

FIG. 4 shows the delivery end of the catheter of FIG. 2 at a targetsite.

FIG. 5 shows the emboli protection device of FIGS. 3 and 4 deployed atthe target site.

FIG. 6 shows the catheter of FIG. 2 with a retrieval end of the catheterin close proximity to the deployed emboli protection device of FIG. 5.

FIG. 7 shows the emboli protection device of FIG. 6 captured within theretrieval end of the catheter of FIG. 2.

FIG. 8 shows an alternative double-ended catheter.

FIG. 9 is a cross-sectional view taken along section line 9-9 of FIG. 8.

FIG. 10 shows another alternative double-ended catheter.

FIG. 11 is a cross-sectional view taken along section line 11-11 of FIG.10.

FIG. 12 shows a double-ended catheter that includes an expandableballoon.

FIG. 12A is a detailed view of a portion of FIG. 12.

FIG. 12B is an alternative balloon catheter configuration.

FIGS. 13-15 show a technique for equipping the catheter of FIG. 12 witha Luer fitting for use in inflating and deflating the expandableballoon.

FIGS. 16 and 17 show packaging techniques for protecting the deliveryend of the catheter of FIG. 2 during shipping.

FIG. 18 shows an alternative double-ended catheter.

FIGS. 19 and 19A show a guide wire loading assist device disposed on analternative double-ended catheter.

FIGS. 19B and 19C show an alternate embodiment of a guide wire loadingassist device.

DETAILED DESCRIPTION OF THE INVENTION

Inventive aspects of the present disclosure relate to intravascularmedical devices having opposite end portions each adapted for insertionwithin the vasculature of a patient. The opposite end portions each havedifferent operating characteristics such that the medical device iscapable of performing different functions depending upon the end of thedevice that is inserted into the patient. It will be appreciated thatthe broad aspects of the present invention are applicable to any numberof different types of intravascular medical devices. Example devicesinclude guide wires, catheters, implant delivery systems, emboliprotection device delivery systems, implant retrieval systems, andemboli protection device retrieval systems.

With reference now to the various drawing figures in which identicalelements are numbered identically throughout, a description is providedof embodiments that are examples of how inventive aspects in accordancewith the principles of the present invention may be practiced. It willbe appreciated that the depicted embodiments are merely exemplary, andare not intended to limit the broad scope of the present invention.

I. General Double Ended Device

FIG. 1 illustrates an intravascular medical device 20 having featuresthat are examples of inventive aspects in accordance with the principlesof the present disclosure. It will be appreciated that the intravascularmedical device 20 can be embodied in a number of different devices suchas catheters, guide wires, embolic filter delivery devices, embolicfilter retrieval devices, as well as other devices.

Referring to FIG. 1, the medical device 20 includes an elongated body 22having first and second opposite end portions 24, 26. The elongated body22 is preferably sufficiently flexible to allow the device to beadvanced through a curving vascular pathway without kinking and withoutpuncturing the vessel wall. The first and second end portions 24 and 26are both capable of leading the elongated member 22 through thevasculature depending upon the direction the elongated member 22 isinserted into the vasculature. The first and second end portions 24 and26 preferably have different operating characteristics. For example, inone embodiment, the first end portion 24 can be more flexible than thesecond end portion 26. In other embodiments, the first and second endportions 24 and 26 can have different pre-formed shapes adapted forfacilitating advancement of the medical device 20 along differentintravascular pathways. In still other embodiments, the first and secondend portions 24 and 26 can be adapted for providing different functions.For example, in one embodiment, the first end portion 24 can be adaptedfor deploying an indwelling medical device such as a stent, graft orembolic protection device, and the second end portion 26 can be adaptedfor retrieving an indwelling medical device such as a stent, graft orembolic protection device.

The elongated member 22 of the medical device 20 includes a main body 28that extends between the first and second end portions 24 and 26. Themain body 28 can have any number of different types of configurations.For example, the main body 28 can have a solid configuration such as asolid wire configuration, a solid polymeric configuration, or acomposite metal and polymeric configuration. In other embodiments, theelongated member 22 can have a tubular configuration defining a singlelumen, or can define a plurality of lumens. In one embodiment, the mainbody 28 includes a metal having “super elastic” properties such asnitinol. The main body 28 can also include materials such as carbonfiber and its composites, liquid crystal polymers, ceramics, andcomposites in general. The elongated member may be coated withhydrophobic, hydrophilic, or biologically active coatings such as polyvinyl pyrrolidone coatings, ePTFE coatings, or heparin coatings. In onenon-limiting embodiment, the elongated member 22 has a length L in therange of 60-300 cm, and an outer diameter D in the range of 0.013″ to0.100″ (0.033 to 0.25 cm).

The end portions 24 and 26 of the medical device can have any number ofdifferent configurations. For example, end portions 24 and 26 caninclude a polymeric material, a metal material, a combined polymer andmetal material, a shape memory material, or a super elastic material.Further, the end portions 24, 26 can include a solid configuration, or atubular configuration defining a single lumen or a multi-lumenconfiguration. Moreover, the end portions 24 and 26 can include constantdiameter embodiments, tapered diameter embodiments, solid wall tubularembodiments, perforated wall tubular embodiments, slotted-wall tubularembodiments, coiled embodiments, and any number of other differentconfigurations. The first and second end portions 24 and 26 can beunitary parts of the main body 28, or can be separate pieces orcomponents that are affixed to the main body 28. It will be appreciatedthat the lengths and diameters of the end portions 24, 26 will varydepending upon their desired operating characteristics. In oneembodiment, the end portions 24, 26 function as flexible guide tipshaving greater flexibility than the main body 28, and differentflexibilities from one another.

II. Double Ended Catheter with Rapid Exchange Features

FIG. 2 illustrates a catheter 100 having features that are examples ofinventive aspects in accordance with the principles of the presentdisclosure. The catheter 100 includes a central shaft 110 having a firstend 112 positioned opposite from a second end 114. A tip in the form ofa flexible delivery sheath 116 is positioned at the first end 112. Theflexible delivery sheath 116 defines an internal pocket 118 (i.e., acompartment, cavity, enclosure, chamber or receptacle) configured forreceiving a preloaded device (e.g., a preloaded embolic protectiondevice such as the filter device 70 shown in FIGS. 3-5). The catheter100 also includes a flexible retrieval sheath 120 positioned at thesecond end 114 of the shaft 110. The flexible retrieval sheath 120defines an internal pocket 122 sized and shaped for receiving a medicaldevice (e.g., an embolic protection device such as the filter device 70of FIGS. 3-5) for retrieval of the medical device after the device hasbeen used.

The shaft 110 of the catheter 100 is preferably sufficiently flexibleand has sufficient column strength to be advanced through thevasculature of a patient. In a preferred embodiment, the shaft 110includes a solid wire coated with an outer layer of a polymericmaterial. However, it will be appreciated that in other embodiments, theshaft could include a tubular metal configuration or otherconfigurations. In one non-limiting embodiment adapted for use incoronary applications, the shaft 110 can have a length in the range of70-170 cm, and more preferably in the range of 100-140 cm. In certainembodiments, the shaft 110 can have an outer diameter D in the range of0.026″-0.040″ (0.066-0.10 cm).

Referring still to FIG. 2, the delivery sheath 116 of the catheterpreferably includes a material that is softer and more pliable than thecentral shaft 110. The flexible design of the delivery sheath 116facilitates advancing the catheter 100 through tortuous vessels whilethe more rigid central shaft 110 can provide pushability. In a preferredembodiment, the delivery sheath 116 is formed of a polymer such as LDPE,MDPE, or PEBAX. In one embodiment, the outer diameter of the deliverysheath can be in the range of 0.026-0.040 inches (0.066-0.10 cm), a wallthickness of the delivery sheath can be in the range of 0.001 to 0.005inches (0.0025 to 0.013 cm), and a length of the delivery sheath can bein the range of 10 to 40 centimeters.

Referring still to FIG. 2, the delivery sheath 116 includes a firstsidewall port 148 and a second sidewall port 150. The first and secondsidewall ports 148, 150 are spaced apart from one another along thelength of the sheath 116. The first sidewall port 148 is located closerto a free end of the sheath 116 than the second sidewall port 150. Theports 148, 150 are preferably skived and dimensioned to allow a distallyand inwardly extending wire to extend from the outside of the sheath 116to the internal pocket 118 at an angle of less than about 10° relativeto a longitudinal axis of the catheter 100. Further details regardingthe configuration of the flexible sheath can be found in U.S. PatentApplication Publication No. 2003/0233117 A1, published Dec. 18, 2003,entitled RAPID EXCHANGE CATHETERS USABLE WITH EMBOLIC PROTECTIONDEVICES, the contents of which are hereby incorporated by referenceherein.

The recovery sheath 120 of the catheter 100 is preferably made of acompliant material that is more flexible than the shaft 110. Preferably,the sheath 120 has sufficient flexibility to allow the sheath 120 totraverse the tortuous pathways typically encountered within thevasculature of a human. Suitable materials for making the sheath 120include thermal plastic polymers, polymer blends and thermal setpolymers such as silicone, or silicone blends with a low durometer. Onesuch material is a 35/40 D PEBAX blend. Any other appropriate compliantmaterials may, however, be used. In one embodiment, the outer diameterof the recovery sheath can be in the range of 0.040-0.060 inches (0.10to 0.15 cm), a wall thickness of the recovery sheath can be in the rangeof 0.001 to 0.005 inches (0.0025 to 0.013 cm), and a length of therecovery sheath can be in the range of 5 to 30 centimeters.

Referring still to FIG. 2, the recovery sheath has an outermost end thatforms a rolled tip 132. The rolled tip 132 is especially designed forcrossing a stented or otherwise constricted region of a blood vessel.The rolled tip 132 can also function to capture an implanted device suchas an embolic protection device. Further details regarding the recoverysheath 120 can be found in U.S. Patent Application Publication No.2002/0111649 A1, published Aug. 15, 2002, entitled ROLLED TIP RECOVERYCATHETER, the contents of which are hereby incorporated by referenceherein.

In certain embodiments, the sheaths 116, 120 can include one or morebands of radiopaque material, or can be filled with radiopaque material.Examples of radiopaque materials include barium sulfate, bismuth subcarbonate, tungsten powder, and the like. The presence of radiopaquematerials facilitates viewing the sheaths under fluoroscopy. The sheaths116, 120 may be coated with hydrophobic, hydrophilic, or biologicallyactive coatings such as poly vinyl pyrrolidone coatings, ePTFE coatings,or heparin coatings.

Use of the catheter 100 will now be described with respect to a coronaryprocedure. However, it will be appreciated that the embodiment can alsobe used for treating other vessels (e.g., carotid, renal, peripheral,and other blood vessels).

In an example of a coronary procedure, a physician first inserts aguidewire (not shown) into the femoral artery of a patient near thegroin, and advances the guidewire through the artery, over the aorta andto a coronary ostium 21. Once the guidewire is in place, a guidecatheter 11 is passed over the guidewire and advanced until a distal endof the guide catheter 11 is located adjacent the coronary ostium 21. Theguidewire (not shown) is then removed. With the guide catheter 11 inplace, a coronary guidewire 19 is inserted into the guide catheter andadvanced into the coronary artery. See FIG. 3. Next, the proximal end ofthe coronary guidewire 19 is inserted (i.e. back-loaded) through thedistal opening of sheath 116 and then the first sidewall port 148 of thedelivery catheter 100.

Prior to insertion of the coronary guidewire 19 through the firstsidewall port 148, an embolic protection device such as an embolicfilter device 70 is preferably pre-loaded within the delivery sheath 116of the catheter 100. The filter device 70 is preferably aself-expandable filter device such as the filter device disclosed inU.S. Pat. No. 6,325,815, the contents of which are hereby incorporatedby reference herein. The filter device 70 includes an expandable filtermesh 71 secured to the distal end of a host wire 74. As shown in FIG. 3,in the pre-loaded configuration, the mesh of the filter device iscompressed in a radially reduced profile configuration within thedelivery sheath 116, and the host wire 74 extends from the mesh materialthrough the second sidewall port 150 of the delivery sheath 116. Thefilter device 70 can be viewed as one type of distal emboli protectionelement. Other distal protection elements which can be included as partof the device are occlusive emboli protection elements, includingexpandable or inflatable elements for blocking fluid flow through avessel.

After the guide wire 19 has been back-loaded through the delivery sheath116, the delivery sheath 116 of the catheter 100 is advanced through theguide catheter 11 along the guidewire 19 until the delivery sheath 116is advanced to the distal tip the guide catheter 11, as shown in FIG. 3.Preferably, the guidewire 19 is then further advanced within thecoronary artery to a point where the distal most tip of the guidewire 19is located at a target site 25 within a coronary artery 23 (e.g., a sitelocated downstream of a treatment site such as an occlusion 27). Thedelivery sheath 116 of the catheter 100 can then be tracked along theguide wire 19 to the target site 25 as shown in FIG. 4. In othermethods, the guidewire 19 and the catheter 100 can be advanced togetheracross the target site with the guidewire 19 providing stiffening forthe catheter 100.

Once the tip of the delivery sheath 116 is located at the target site25, the guidewire 19 is retracted proximally through the distal sidewallport 148. With the guidewire no longer present within the deliverysheath 116, the filter device 70 can be distally advanced to the tip ofthe delivery sheath 116 and then from the delivery sheath 116. Forexample, the embolic filter 70 can be advanced from the sheath 116 byproximally retracting the catheter 100 while the host wire 74 is held inplace by the treating physician. By retracting the catheter 100, thesheath 116 retracts relative to the filter device 70 thereby exposingthe filter device 70 and allowing the filter device 70 to expandradially so as to provide filtration across the entire cross sectionalarea of the vessel as shown in FIG. 5.

Once the filter device 70 is in place, the catheter 100 can be retractedfrom the patient, and an interventional device (e.g., a balloonangioplasty catheter, a stent delivery catheter, an atherectomy device,a thrombectomy device or any other device) can be introduced over thehost wire 74 and used to treat the treatment site. As the treatment siteis treated, any emboli generated during the treatment process arecaptured by the filter 70.

After the treatment process has been completed, the interventionaldevice is removed and the catheter 100 is reintroduced over the hostwire 74. However, when reintroduced, the catheter 100 is reversed suchthat the recovery sheath 120 functions as the distal most tip of thecatheter 100. Preferably, the host wire 74 is passed through theinterior of the recovery sheath 120 as shown in FIG. 6. The catheter 100is advanced until the rolled end 132 is positioned immediately proximalto the filter device 70. The host wire 74 is then pulled in a proximaldirection causing a proximal end of the filter device 70 to contact therolled tip 132. As the filter device 70 contacts the rolled tip 132, therolled tip 132 is urged elastically toward an open orientation in whichthe filter device 70 can be passed into the recovery sheath 120. Oncethe filter device 70 has been fully drawn into the sheath 120 as shownin FIG. 7, the rolled tip 132 reaches a point where it ceases to beengaged by the filter device 70, and it elastically returns to itsundeflected configuration. It will be appreciated that the resilientmaterial forming the sheath 120 prevents the escape of emboli when thefilter device 70 is captured. Preferably, at least a portion of the wallof the sheath 120 closely encompasses the periphery of the filter device70 and assumes the shape of the periphery. As a result, emboli areprevented from passing between the periphery of the filter device 70 andthe wall of the sheath 120. Alternatively, the filter device 70 can bepartly drawn into the recovery sheath 120 such that only the enlargedproximal opening of the filter is within the sheath.

Once the filter device is positioned within the recovery sheath 120,both the host wire 74 and the catheter 100 can be withdrawn from thepatient together as a unit. Thereafter, the procedure is completed byremoving the guide catheter 22 from the patient.

III. Over-the-Wire Double Ended Catheter

FIGS. 8 and 9 illustrate an alternative catheter 200 having a similarconfiguration as the catheter 100 of FIG. 2, except the solid centralshaft 110 has been replaced with a double lumen configuration 210 havinga first end 212 and a second end 214. The catheter 200 includes adelivery sheath 116 positioned at the first end 212 and a recoverysheath 120 positioned at the second end 114. The double lumenconfiguration 210 includes a first tube 211 that is coaxial with thedelivery sheath 116, and a second tube 213 that is coaxial with therecovery sheath 120. It will be appreciated that the tubes of the doublelumen configuration 210 are coupled together and are sufficientlyflexible to be able to be passed through a tortuous vascular pathway,and also have sufficient column stiffness to allow the catheter 200 tobe pushed through the vasculature. It will be appreciated that the tubescan be manufactured using any number of known techniques. For example,the tubular structures may be extruded or coextruded in the crosssectional shape shown in FIG. 9 or in any number of alternative crosssections, for example those known in the art as double D, smile, orother configurations. Alternatively, the tubular structures can bemanufactured from individual tubes of polymer such as polyimide or asuper elastic material such as nitinol and held together with adhesivesor a thin tube that surrounds both single lumen tubes. It will beappreciated that any number of different types of material can be usedto form double lumen configuration 210.

Similar to the previous embodiment, the catheter 200 can be used to bothdeliver a device such as an embolic protection device, and to retrieve adevice such as an embolic protection device. The catheter 200 is used ina manner similar to the catheter 100, except the catheter 200 does nothave rapid exchange capabilities. Instead, when the catheter 200 is usedwith the delivery sheath 116 as the distal end, a guidewire is passedthrough the entire length of the first tube 211. Similarly, when theretrieval sheath 120 is used as the distal end of the catheter 200, aguidewire or wire such as host wire 74 is passed completely through thesecond tube 213 of the double lumen configuration 210.

IV. Double Ended Catheter with Combined Rapid Exchange and Over-the-WireConfiguration

FIGS. 10 and 11 illustrate another catheter 300 having features that areexamples of inventive aspects in accordance with the principles of thepresent disclosure. Similar to the previous embodiments, the catheter300 includes a delivery sheath 116 positioned at one end, and a recoverysheath 120 positioned at the opposite end. The delivery sheath 116 andthe recovery sheath 120 are interconnected by an elongated centralstructure 310 that includes a solid shaft 350 coupled to a tubular shaft352. The solid shaft 350 is connected to the recovery sheath 120, andthe tubular shaft 352 is connected to the delivery sheath 116. Theelongated central structure is sufficiently flexible to bend through thecontours of a tortuous vascular pathway, and also include sufficientcolumn strength to allow the catheter 300 to be pushed through thepathway. The tubular shaft structure 352 has a central lumen in fluidcommunication with the pocket 118 of the delivery sheath 116.

It will be appreciated that the catheter 300 can be used to deliverdevices such as embolic protection devices in much the same way as theprevious two embodiments. However, when delivering an embolic protectiondevice using the delivery sheath 116, the delivery sheath 116 as well asthe entire tubular shaft 352 would typically be passed over a guidewire.In contrast, when the catheter 300 is used as a retrieval device, thecatheter 300 can be used as a rapid exchange catheter in which aguidewire or wire is not passed through the entire catheter, but insteadonly passes through the distal tip (e.g., the recovery sheath portion120 of the catheter).

V. Double Ended Catheter with Balloon

FIG. 12 shows another catheter 400 having features that are examples ofinventive aspects in accordance with the principles of the presentdisclosure. The catheter 400 includes a delivery sheath 116 positionedat one end and a recovery sheath 120 positioned at the opposite end. Thedelivery sheath 116 and the recovery sheath 120 are interconnected by acentral elongated member 410. The elongated member 410 includes a solidshaft 411 connected to the recovery sheath 120, and a tubular shaft 413connected to the delivery sheath 116. The tubular shaft 413 defines acentral lumen 415 that extends from a first end 417 of the tubular shaftto the delivery sheath 116. The lumen is preferably sealed so as to notbe in fluid communication with the interior of the delivery sheath 116.The delivery sheath 116 includes a guidewire port 148 and a host wireport 150.

Referring still to FIG. 12, a balloon such as an angioplasty balloon ora low pressure occlusion balloon 419 is provided on the tubular shaft413 adjacent to the delivery sheath 116. The balloon 419 is in fluidcommunication with the lumen 415 of the tubular shaft 413. The first end417 of the tubular shaft 413 is sealed by a septum or other seal 421.The septum or seal 421 can include multiple membranes 421 a, 421 b (seeFIG. 12A) bonded together at a perimeter of the membranes. The membrane421 a can have a self-closing slit 425 while membrane 421 b can have acentral hole that seals against a blunt needle. Either membrane can havea rim 427 that can be sealed to lumen 415 of tubular shaft 413. Asyringe with a blunt needle can be used to inject fluid into the lumenthrough the seal 421 to inflate the balloon 419.

Other techniques can also be used to provide fluid into the lumen. Forexample, the first end 417 of the tubular shaft 413 can include a sideport in fluid communication with a Luer fitting. The Luer fittingprovides a connection location for attaching an inflation device. TuohyBorst fittings can be secured to the tubular shaft at locations distalto and proximal to the side port to provide a seal between the Luerfitting and the catheter body. The Tuohy Borst fittings can alsoreferred to as hemostatic valves.

Additionally, a Luer lock fitting can be used to provide fluid to thelumen 415. For example, as shown in FIG. 13, the tubular shaft 413 caninclude an elongated slot 433 adjacent the first end in which a Luerlock fitting 435 (shown in FIGS. 14 and 15) can be inserted. FIG. 14shows the Luer lock fitting 435 partially inserted within the slot 433.A stem 437 of the lock fitting 435 fits within the lumen 415.Preferably, the stem 437 snugly fits within the lumen 415 such thatfriction between the stem 437 and the wall of the tubular shaft 413function to provide a fluid tight seal about the stem 437. A rounded end439 of the lock fitting 435 also fits within the slot 433 such that theLuer fitting 435 snaps into a locked or seated position as shown in FIG.15. The Luer fitting 435 provides an attachment location for attaching aballoon inflation apparatus to the catheter.

It should also be appreciated that the balloon shown in FIG. 12 couldalternatively be positioned on the delivery sheath 116 of catheter 400by those skilled in the art. See, for example, FIG. 12B.

The catheter of FIG. 12B can be used in a manner that helps to preventdistal migration of emboli during embolic filter passage across atreatment site. For example, the catheter can be used as described forcatheter 100 in connection with FIGS. 3-7. However, the catheter ispreloaded with an actuator style embolic protection device such as thatdescribed in U.S. Pat. No. 6,520,978 B1, the contents of which arehereby incorporated by reference herein. Prior to crossing the treatmentsite, the catheter balloon 419 is inflated to a pressure sufficient tosubstantially impede blood flow across the treatment site. After ballooninflation, the guidewire 19 is withdrawn and the embolic filter isadvanced across the treatment site in a collapsed diameter. Importantly,emboli liberated by the embolic filter during treatment site passagecannot be transported distally because the inflated balloon 419 preventsdistal blood flow and distal transport of emboli within the flow stream.After crossing the treatment site, the actuating style filter isactuated to cause it to diametrically enlarge and position the filteracross the vessel cross sectional area. At this point, the balloon 419is deflated and flow is restored, causing emboli liberated duringtreatment site crossing to be transported to and captured by the filter.The catheter can now be removed and the treatment site treated.Alternatively, the catheter can be advanced and the balloon used totreat a lesion, followed by balloon deflation and capture of releasedemboli in the filter.

While a balloon has been shown, it will be appreciated that inalternative embodiments, the catheter could include openings fordelivering a substance (e.g., a medicine, dye, or other substance) tothe vasculature of a patient.

VI. Protective Packaging

FIG. 16 illustrates a system 600 for protecting the delivery sheath 116during shipping. The system includes an outer protective sheath 610mounted over the exterior of the delivery sheath 116. A stylette 615extends into the tip of the delivery sheath 116, through the firstsidewall port 148 and along the outer surface of the catheter. Thestylette provides rigidity for protecting the delivery sheath 116. Aloop 620 is provided for pulling the stylette 615 from the sheath 116.

FIG. 17 shows an alternative stylette 600′ having a flag 650 as comparedto a loop 620. Method of use instructions for the catheter can beprinted on the flag 650.

Alternatively the protective packaging can be applied to the recoverysheath 120, or to both the delivery sheath 116 and the recovery sheath120. It will be further appreciated that it is not necessary to utilizeboth a stylette and protective sheath; they can be used alone as well asin combination at either or both ends of the catheter.

VII. Double Ended Catheter with Rapid Exchange Features and VariableDiameter

FIG. 18 illustrates a catheter 700 similar to the catheter of FIG. 2.The catheter 700 includes a central shaft 710 having a first end 712positioned opposite from a second end 714. A tip in the form of aflexible delivery sheath 716 is positioned at the first end 712. Theflexible delivery sheath 716 defines an internal pocket 718 (i.e., acompartment, cavity, enclosure, chamber or receptacle) configured forreceiving a preloaded device (e.g., a preloaded embolic protectiondevice such as the filter device 770 shown in FIG. 18). The filterdevice 770 includes an expandable filter mesh 771 secured to the distalend of a host wire 774. The catheter 700 also includes a flexibleretrieval sheath 720 positioned at the second end 714 of the shaft 710.The flexible retrieval sheath 720 defines an internal pocket 722 sizedand shaped for receiving a medical device (e.g., an embolic protectiondevice such as the filter device 770 of FIG. 18) for retrieval of themedical device after the device has been used.

The delivery sheath 716 includes a first sidewall port 748 and a secondsidewall port 750. The first and second sidewall ports 748, 750 arespaced apart from one another along the length of the sheath 716. Thefirst sidewall port 748 is located closer to a free end of the sheath716 than the second sidewall port 750. The ports 748, 750 are preferablyskived and dimensioned to allow a distally and inwardly extending wireto extend from the outside of the sheath 716 to the internal pocket 718at an angle of less than about 10° relative to a longitudinal axis ofthe catheter 700.

The catheter 700 includes a lumen portion 740 of a narrower diameterthan the internal pocket 718. The diameter of the internal pocket 718 isreduced at constriction 744. Constriction 744 prevents proximal movementof the filter device 770 and creates a preloading stop or “holding zone”location for the filter device 770. This location is distal of theconstriction 744 and proximal of the first sidewall port 748 to preventinteraction of the guidewire 719 with the filter 770.

VIII. Guide Wire Loading Assist Device

FIGS. 19 and 19A illustrate a guide wire loading assist device 854. Thedevice 854 has a port 856 that lines up with sidewall port 748 ofcatheter 700. As shown in FIG. 19, assist device 854 bends catheter 700to make loading of the guide wire 719 easier. In some embodiments theassist device 854 bends catheter 700 by having a pre-formed shape andstiffness sufficient to overcome the shape and stiffness of catheter700. Specifically, the device 854 ensures that the guide wire will exitthe correct port without interacting with the filter 770.

The device 854 may be loaded prior to packaging or provided as aseparate piece within the packaging for the physician to place on thecatheter 700 prior to introducing the guide wire 719. A slit 858 thatruns from port 856 to the proximal end of the device 854 allows for easyremoval of the device once the guide wire is in place. Alternatively, aslit may run from port 856 to distal end of the device 854, or bothproximal and distal slits may be provided. In some embodiments, slotsare used rather than slits. In another embodiment a pull tab of a sizesufficient for a device user to grasp is provided at one or both ends ofdevice 854 for the purpose of facilitating device 854 removal fromcatheter 700. In some embodiments the device 854 is comprised of apolymer having bright color so as to facilitate rapid identification bythe device user. After the device 854 is removed, the catheter revertsto its original conformation.

The device 854 preferably is made of a heat formable material formedwith a slight bend. Suitable heat formable materials include polymerssuch as LDPE, MDPE, and PEBAX. The device 854 can also be injectionmolded.

FIGS. 19B and 19C illustrate an alternate embodiment of a guide wireloading assist device 854. The device 854 has a port 856 that lines upwith sidewall port 748 of catheter 700. As shown in FIG. 19, assistdevice 854 bends catheter 700 to make loading of the guide wire 719easier. In some embodiments the assist device 854 bends catheter 700 byhaving a pre-formed shape and stiffness sufficient to overcome the shapeand stiffness of catheter 700. Specifically, the device 854 ensures thatthe guide wire will exit the correct port without interacting with thefilter 770.

The device 854 may be loaded prior to packaging or provided as aseparate piece within the packaging for the physician to place on thecatheter 700 prior to introducing the guide wire 719. A slit 958 runsfrom port 856 to the distal end of the device 854 and allows for easyremoval of the device once the guide wire is in place. A slot runs froma location proximal to port 856 to a proximal end of the device 854. Theaxis of proximal slotted end of device 854 is oriented approximately 25°away from the axis of the device 854 in the region of port 856. Theproximal slotted end of device 854 functions as a pull tab of a sizesufficient for a device user to grasp for removal of device 854 fromcatheter 700. In some embodiments the device 854 is comprised of apolymer having bright color so as to facilitate rapid identification bythe device user. After the device 854 is removed, the catheter revertsto its original conformation.

The above description and the drawings are provided for the purpose ofdescribing embodiments of the invention and are not intended to limitthe scope of the invention in any way. It will be apparent to thoseskilled in the art that various modifications and variations can be madewithout departing from the spirit or scope of the invention. Thus, it isintended that the present invention cover the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. A catheter comprising: an elongated memberconfigured to be advanced along a vascular path of a patient, theelongated member having opposite first and second ends and correspondingfirst and second end portions, the first end and second ends both beingadapted for intravascular insertion, the elongated member having alength and the distance between the first and second ends being theentire length of the catheter, and the first end portion comprising adelivery sheath and the second end portion comprising a retrievalsheath, wherein the delivery sheath comprises first and second sidewallports adapted for receiving wires, a distance from the first sidewallport to the first end being less than a distance from the secondsidewall port to the first end, the elongated member further comprisinga lumen between the first end of the elongated member and the first andsecond sidewall ports, the lumen having a first diameter at the firstsidewall port and a second, reduced diameter at a point between thefirst and second sidewall ports.
 2. The catheter of claim 1, wherein thedelivery sheath comprises at least one sidewall port adapted forreceiving a wire, the catheter having a lumen between the first end andthe at least one sidewall port.
 3. The catheter of claim 2, wherein thesidewall port is skived.
 4. The catheter of claim 1, wherein thesidewall ports are skived.
 5. The catheter of claim 1, wherein theretrieval sheath comprises a rolled tip.
 6. An assembly comprising aguide wire and a catheter of claim
 1. 7. The catheter of claim 1,further comprising a guide wire.
 8. The catheter of claim 1, wherein anembolic protection device is adapted to be delivered and retrieved bythe elongate member.
 9. The catheter of claim 1, wherein an embolicprotection device is a filter.
 10. The catheter of claim 9, wherein thefilter is self-expandable.
 11. The catheter of claim 1, wherein anembolic protection device is disposed in a lumen of the elongatedmember.